Risk factors for acute myelogenous leukemia

A risk factor is something (such as a behaviour, substance or condition) that increases the risk of developing cancer. Most cancers are the result of many risk factors, but sometimes acute myelogenous leukemia (AML) develops in people who don’t have any of the risk factors described below.

The risk of developing AML increases with age. The average age at diagnosis is 65 years. More men than women develop AML.

Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.

Known risk factors

There is convincing evidence that the following factors increase your risk for AML.

Genetic syndromes

Genetic syndromes are groups of symptoms caused by a change, or mutation, in one or more genes. They are passed from parents to children. Having certain genetic syndromes can increase the risk of developing AML, especially childhood AML. The following genetic syndromes are associated with an increased risk for AML. Other genetic syndromes may also increase the risk of AML.

Down syndrome is a condition caused by an extra (third) copy of chromosome 21. It causes different birth defects, intellectual disability, a characteristic facial appearance and poor muscle tone in infancy. People with Down syndrome have a higher risk of developing several medical conditions, including childhood leukemia.

Fanconi anemia is a condition that mainly affects the bone marrow so that it doesn’t make enough healthy red blood cells, white blood cells and platelets. People with Fanconi anemia have a higher risk of developing leukemia.

Bloom syndrome is a condition caused by a large number of abnormal chromosomes. People with Bloom syndrome are usually smaller than average, have a high-pitched voice and a characteristic facial appearance. People with Bloom syndrome have a high risk of developing different types of cancer, including AML.

Ataxia-telangiectasia (AT) is a rare condition that affects the nervous system, immune system and other body systems. People with AT have problems with walking, balance and coordination. They often have a weakened immune system and a higher risk of developing cancer, particularly lymphoma and leukemia.

Neurofibromatosis type 1 (von Recklinghausen disease) is a condition that causes tumours to start in nerve tissue. These tumours form in the skin, just under the skin and in cranial and spinal cord nerves. People with neurofibromatosis type 1 have a higher risk of developing certain cancers, including leukemia.

Shwachman-Diamond syndrome is a condition that affects many parts of the body, including the bone marrow, pancreas and skeletal system. People with Shwachman-Diamond syndrome often have low levels of red blood cells, white blood cells and platelets. This causes more infections, fatigue, weakness and easy bruising or bleeding. People with Shwachman-Diamond syndrome also have a higher risk of developing AML.

Dyskeratosis congenital is a condition that causes abnormally shaped fingernails and toenails, a lacy rash on the face and chest, white patches in the mouth and often bone marrow failure. People with dyskeratosis congenital have a risk for myelodysplastic syndromes (MDS) and cancers such as leukemia.

Kostmann syndrome is also known as severe congenital neutropenia. It is a condition that causes very low white blood cell counts. People with Kostmann syndrome have a higher risk for infections, myelodysplastic syndromes (MDS) and cancers such as leukemia.

Wiskott-Aldrich syndrome is a condition that affects blood cells and cells of the immune system. People with Wiskott-Aldrich syndrome have fewer platelets, which can cause easy bruising and bleeding. They also have a higher risk for infection because some immune cells, such as T cells and B cells, do not work properly. People with Wiskott-Aldrich syndrome have a higher risk of developing some types of cancer, such as leukemia.

Li-Fraumeni syndrome is a rare condition that greatly increases the risk of developing several types of cancer, including breast cancer, osteosarcoma, soft tissue sarcomas, brain cancer and leukemia.

Klinefelter syndrome is a condition caused by an extra copy of the X chromosome in males. It affects male sexual development. Klinefelter syndrome also increases the risk of leukemia.

High doses of radiation

Exposure to high doses of radiation is a risk factor for AML. Survivors of the atomic bomb explosions in Japan during the Second World War have a higher risk of developing AML. People exposed to radiation from nuclear reactor accidents also have a higher risk of developing AML.

Smoking

Smoking tobacco has been linked to the development of AML. About 20% of AML cases may be linked to exposure to tobacco smoke. This may be related to the presence of benzene in tobacco.

Previous radiation therapy

Radiation therapy given to treat cancer or other health conditions increases the risk for AML. The risk of developing AML is greater if both chemotherapy and radiation were used in treatment.

People treated with radiation therapy for the following cancers have a higher risk for AML:

Hodgkin lymphoma

non-Hodgkin lymphoma

breast cancer

From 1935 to 1954, radiation therapy was used to treat ankylosing spondylitis. People treated with radiation for this condition had the highest risk for developing AML 3–5 years after treatment.

Menorrhagia is abnormally heavy menstrual flow. In the past, radiation therapy was used to treat this and other gynecological conditions. Radiation is no longer used to treat these conditions.

Previous chemotherapy

Certain types of chemotherapy given to treat children or adults with cancer can increase the risk of developing AML. The risk is greater if both chemotherapy and radiation were used in treatment.

People treated with chemotherapy for the following cancers have a higher risk for AML:

Hodgkin lymphoma

non-Hodgkin lymphoma

multiple myeloma

ovarian cancer

breast cancer

childhood acute lymphocytic leukemia (ALL)

Exposure to benzene

Benzene is found in unleaded gasoline and is used by the chemical industry. People may be exposed to benzene in the workplace, in the general environment and through the use of certain products. Exposure to benzene increases the risk of developing AML.

Exposure to formaldehyde

Studies have shown that exposure to formaldehyde increases the risk of myelogenous leukemias. Factory workers, chemical workers, embalmers and other people may be exposed to formaldehyde in the workplace. Embalmers tend to have longer-term exposure and higher overall exposure to formaldehyde than industry workers. People with higher exposure to formaldehyde (both exposure level or length of exposure) have an increased risk of developing AML.

History of a blood disorder

People with a history of the following blood disorders have a higher risk of developing AML:

Myelodysplastic syndrome (MDS) is the most common blood disorder that makes a person more likely to develop AML.

Chronic myelogenous leukemia (CML) eventually transforms into, and cannot be told apart from, AML. But not everyone with AML has CML first.

Possible risk factors

Being overweight or obese is a possible risk factor for AML. This means that it has been linked with AML, but there is not enough evidence to show that it is a known risk factor.

People who are overweight or obese may have a higher risk of developing certain types of cancer, including leukemia, than people with a normal body weight.

Unknown risk factors

It isn’t known whether or not the following factors are linked with AML. It may be that researchers can’t show a definite link or that studies have had different results. Further study is needed to see if the following are risk factors for AML: